Xu Zelin, Guo Dingcheng, Liu Ziqiang, Wang Zhiyan, Gu Zhi, Wang Da, Yao Xiayin
State Key Laboratory of Advanced Special Steel, School of Materials Science and Engineering, Shanghai University, 99 Shangda Road, Baoshan District, Shanghai, 20444, P. R. China.
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 1219 Zhongguan West Road, Zhenhai District, Ningbo, Zhejiang Province, 315201, P. R. China.
Chem Asian J. 2022 Nov 2;17(21):e202200712. doi: 10.1002/asia.202200712. Epub 2022 Sep 19.
Lithium-oxygen batteries have received great research interest owing to their ultrahigh theoretical energy density and are considered as one of the promising secondary batteries. However, there are still some challenges in their practical application, like liquid organic electrolyte evaporation in the semi-open system and instability in the high-voltage oxidizing environment. In this work, a cellulose acetate-based gel polymer electrolyte (CA@GPE) is proposed, whose cross-linked microporous structure ensures the ultrahigh liquid electrolyte uptake of 2391%. The prepared CA@GPE exhibits a high lithium-ion transference number of 0.595, a satisfying ionic conductivity of 0.47 mS cm and a wide electrochemical stability window up to 5.0 V. The Li//Li symmetric cell employing CA@GPE could cycle stably over 1200 h. The lithium-oxygen battery with CA@GPE presents a superb cycling lifetime of 370 cycles at 0.1 mA cm under 0.25 mAh cm . This work offers a possible strategy to realize long-cycling stability lithium-oxygen batteries.
锂氧电池因其超高的理论能量密度而受到了广泛的研究关注，并被视为最有前景的二次电池之一。然而，其实际应用仍面临一些挑战，如半开放体系中液体有机电解质的蒸发以及在高电压氧化环境中的不稳定性。在这项工作中，我们提出了一种基于醋酸纤维素的凝胶聚合物电解质（CA@GPE），其交联微孔结构确保了2391%的超高液体电解质吸收率。制备的CA@GPE表现出0.595的高锂离子迁移数、0.47 mS cm的令人满意的离子电导率以及高达5.0 V的宽电化学稳定窗口。采用CA@GPE的Li//Li对称电池可稳定循环超过1200 h。具有CA@GPE的锂氧电池在0.25 mAh cm 下，0.1 mA cm 时呈现出370次循环的超长循环寿命。这项工作为实现长循环稳定性的锂氧电池提供了一种可能的策略。
